class FastIO {
 public:
  FastIO& operator>>(auto& x) {
    char c = getchar();
    bool neg = false;
    for (; !isdigit(c); c = getchar())
      if (c == '-') neg = true;
    for (x = 0; isdigit(c); x = x * 10 + c - '0', c = getchar());
    if (neg) x = -x;
    return *this;
  }
} fio;